The present invention relates to an input/output connector intended to be surface-mounted on a printed circuit board PCB comprising, among other things, an insulating housing on whose lateral parts are fixed two positioning dogs to be soldered to the PCB, contacts to be soldered to the PCB. It also relates to the process for mounting the said connector.
In a general and known manner, the input/output connector of a portable communication device, for example a mobile telephone, which is of very small dimensions, is surface-mounted on a printed circuit board PCB. For the sake of conciseness and simplification the printed circuit board will hereafter be referred to as PCB ("Printed Circuit Board"), the term commonly used by those skilled in the art. This connector thus makes it possible to connect and disconnect an exterior electronic device, equipped with a complementary connector, to the portable communication device so as to permit dialogue between the two devices, or the testing of the functions or components installed on the PCB. Given the very small size of the connector used for this type of application and the vital need for highly accurate positioning during the mounting thereof so that the bearing plane of the connector coincides or at least almost coincides with the plane of the PCB, specific means for positioning and fixing the connector as well as the contacts must be provided. Thus, when implementing the product, the surface-mounting of the component, and also throughout the lifetime of the portable device, sometimes under severe handling conditions, all the contacts of the complementary connectors should be able to engage with one another and ensure that the contact pressure is adequate for good electrical transmission. Thus, it has been observed that for this function to be effective, it is necessary for the bearing plane of the connector to coincide or at least almost coincide with the plane of the PCB. In fact, this coplanarity provides for an efficient answer to a requirement for so-called coflatness, necessary for the implementation of the surface-mounting process, which requirement implies that any contact must be located within a maximum tolerance interval, which is desired to be small (for example of the order of 0.1 mm), in relation to the plane of bearing of the connector on the PCB, which bearing plane defines the plane of reference for the said coflatness.
International application WO 96/07221 describes such a connector which uses metal soldering fixings intended for holding it and setting it in position on the PCB. However, the use of such fixings has a considerable drawback since it does not allow the abovementioned necessary accuracy and hence the coflatness requirement to be met sufficiently rigorously. This is because the fixings described rest on the PCB over the whole of the surface of their base whilst, moreover, the connector rests at the rear on the said PCB either on a mounting surface or on a set of contacts. Thus, three surfaces which are independent and consequently whose probability of being coplanar is extremely small, the two surfaces of the bases of the fixings and the surface via which the rear of the connector rests on the PCB, are in this case involved in determining the plane of bearing of the connector on the PCB. Moreover, the dimensional constraints of the product do not allow sufficiently accurate guiding of the contacts. All of the above implies that this bearing plane evidently cannot be determined in an accurate and reproducible manner and yet, as was stated earlier, this bearing plane defines the plane of reference for the coflatness of the contacts and thus a considerable scatter is created as regards the coflatness.